Recording-2025-02-24T00_42_23.193Z

Inheritance Patterns

Mendelian Inheritance

• Parents' genotypes determine offspring's traits.

• Traits can be red or white based on genotype.

Complex Inheritance

• Real-life examples demonstrate deviations from simple Mendelian inheritance.

• Example: Crossing a red cow with a white bull results in roan offspring, showcasing both colors, a pattern known as codominance.

Codominance vs Incomplete Dominance

• Codominance: Both parental traits are fully expressed (e.g., red and white coat).

• Example: Roan cow or bull expresses both red and white colors.

• Incomplete Dominance: A blend of traits creates a new intermediate phenotype (e.g., crossing black and white cats results in gray cats).

• Example: Red and white Camellias produce pink flowers.

• Important to distinguish between codominance and incomplete dominance:

  • Codominance = both traits visible.

  • Incomplete dominance = mixed phenotype.

Activity Instructions

• Students instructed to use devices for Gizmo simulation.

• Complete worksheet prior to starting with Gizmo.

• Remember to visualize colors accurately (black = red in diagrams).

Discussion Points

• Students engaged in discussing possible offspring outcomes based on different genotypes.

• Questions on predicting mixtures of traits, encouraging analytical thinking.

Key Genetic Concepts

Alleles and Genotypes

• Definition: Alleles are different versions of a gene.

• Example: FW (white) and FR (red) are alleles of the feather color gene.

Phenotypes

• Definition: An organism's observable characteristics.

• Offspring's phenotypes described as colorful based on mixed parent traits.

Experiment Results

• Results indicate combinations of genotypes: F r F w and F w F w observed in chicken breeding experiments.

• Offspring from combinations of traits do not produce homozygous red chickens due to presence of a white chicken parent.

Difference in Inheritance Patterns

• Inheritance patterns differ in expression of alleles:

  • In dominant/recessive traits, the dominant allele overshadows the recessive one.

  • In codominance, both alleles express simultaneously without one overshadowing the other.

Homework Assignments

• Complete pages three and work on unit three project, "Journey of a Photon."

• Emphasis on project completion and submission guidelines.

• Reminders about quality and integrity of work submitted.